1. Technical Field of the Invention
This invention broadly relates to an apparatus for and methods of lifting a load. The invention more particularly relates to lifting a load which occupies a relatively large volume in relation to the weight thereof, wherein the density of such a load is generally considered to be "low". Such loads are sometimes referred to as being "bulky." Accordingly, this invention is useful to lift bulky loads which are difficult to handle more due to the fact of the volume and shape of the load rather than due to the weight thereof. This invention still more particularly relates to an apparatus and to methods of using the apparatus for lifting a bulky load positioned at one location and then transporting the load to and placing it an another location.
2. Description of the Prior Art and Problems Solved
A farm crop which is grown in virtually every agricultural area of the United States and, indeed, throughout the entire world, is hay or some other type of discrete grass or fodder material. The hay, to be useful, is ordinarily severed from the land and then bundled in the field into compact forms which are then lifted in the field, in the bundled form, and transported, as such, to some remote location for storage and subsequent use. The uses, which are not a part of this invention, are well known to include animal feed, bedding, plant mulch as well as a number of other uses. It is important to realize that the farmer who grows the crop of hay cannot ordinarily receive revenue or value from it unless it is first moved from the field and placed in a storage location by utilizing some method which is simple and, preferably, economically attractive.
Methods of severing, i.e. cutting, hay in the field are well known in the art. It is also known to sweep, i.e. rake, the cut hay into windrows to facilitate the drying thereof and, thereafter, to gather the windrows and compress the hay into bundles called bales for subsequent removal from the field. Some bales, i.e. "small bales", exist in a shape and weight which permit a person to physically lift and handle them without resort to mechanical lifting apparatus. However, due, perhaps, to lack of sufficient labor force and/or economies of scale, it has become the practice to form bales which are of such large volume and weight that the lifting and movement thereof requires the use of specialized equipment. In some cases, the large bales are cylindrical in shape, have a diameter in the range of from about 48 to about 50 inches, or more, a length of 4 to 5 feet and weigh in the range of from about 800 to about 1000 pounds. Such bales are known as "round" bales. Other large bales of similar weight are cubical in shape and are called "square" bales. Such large bales are the equivalent in weight to about 10 to 20 small bales.
The prior art has developed apparatus for lifting and transporting large bales. Such apparatus, referred to as "loaders", are designed to be employed at the front end of a field work vehicle, such as a farm tractor. Loaders generally feature a structure comprising two boom arms, each pivoted at the proximal end thereof to the middle of the tractor chassis, a frame, which is hinged at its bottom to the distal end of each boom arm, and a spike rigidly attached to the frame. It is apparent from the description of the loader that the spike does not slide on, or otherwise move relative to, the frame. The spike is of sufficient length and diameter to completely pierce the bale. The weight of the bale is thus transferred from spike to frame to boom arms to chassis to ground. In the prior art apparatus, the boom arms are connected to hydraulic rams which are solely dedicated to lifting and lowering the boom arms relative to the chassis, and the frame is connected to other hydraulic rams which are solely dedicated to rotating the frame about the above mentioned hinge at the distal ends of the boom arms. In operation, the prior art apparatus described requires the frame to be independently lifted from the ground by the boom arms, and the frame to be independently rotated around the mentioned hinge. The frame must be rotated about the hinge because the ends of the boom arms, to which the frame is hinged, move in a curve. The frame is thus independently controlled to level the spike to help retain the bale on the spike during the lift and subsequent transport.
It is apparent that the above described prior art apparatus is not simple and requires the services of a skilled operator to manipulate the dedicated power sources to maintain proper control of the lift and leveling functions involved in a lift and transport operation.
Another prior art apparatus employs a planar frame having rigidly attached thereto a spike for piercing a bale. The frame is ordinarily mounted on a trailer which is pulled by a vehicle, such as a truck, or mounted on the truck itself. The frame of this type apparatus is hinged at the bottom thereof to the trailer or truck, such that upon the application of force to the frame, at a point above the hinge, the frame itself does not lift from the truck or trailer mounting, but does rotate about the hinge as an axis whereby the frame tilts to thereby cause the spike and bale to rotate and thus to lift the load from the ground. It is important to note that the base of the frame at the hinge is, at all times, in contact with the chassis support, i.e. the base of the frame does not break contact with the trailer or the truck. It is further to be noted that the spike does not slide on, or otherwise move relative to, the frame. The power source to supply the force to tilt the frame can be as complicated as a set of hydraulically operated rams or as simple as a hand-powered winch and cable system. The apparatus thus described is, mechanically, simple and easy to use, but rather limited in lifting operations. It is, accordingly, inexpensive as compared to the loader described previously.
There, accordingly, exists a need for an apparatus for and a method of lifting and moving bulky loads which is as useful as the prior art loader, but which does not require dedicated power sources or a skilled operator to manipulate complicated controls and which is as mechanically simple as the described truck mounted frame.